var fxNow, timerId,
rfxtypes = /^(?:toggle|show|hide)$/,
rfxnum = new RegExp( "^(?:([+-])=|)(" + core_pnum + ")([a-z%]*)$", "i" ),
rrun = /queueHooks$/,
animationPrefilters = [ defaultPrefilter ],
tweeners = {
"*": [function( prop, value ) {
var end, unit,
tween = this.createTween( prop, value ),
parts = rfxnum.exec( value ),
target = tween.cur(),
start = +target || 0,
scale = 1,
maxIterations = 20;
if ( parts ) {
end = +parts[2];
unit = parts[3] || ( jQuery.cssNumber[ prop ] ? "" : "px" );
// We need to compute starting value
if ( unit !== "px" && start ) {
// Iteratively approximate from a nonzero starting point
// Prefer the current property, because this process will be trivial if it uses the same units
// Fallback to end or a simple constant
start = jQuery.css( tween.elem, prop, true ) || end || 1;
do {
// If previous iteration zeroed out, double until we get *something*
// Use a string for doubling factor so we don't accidentally see scale as unchanged below
scale = scale || ".5";
// Adjust and apply
start = start / scale;
jQuery.style( tween.elem, prop, start + unit );
// Update scale, tolerating zero or NaN from tween.cur()
// And breaking the loop if scale is unchanged or perfect, or if we've just had enough
} while ( scale !== (scale = tween.cur() / target) && scale !== 1 && --maxIterations );
}
tween.unit = unit;
tween.start = start;
// If a +=/-= token was provided, we're doing a relative animation
tween.end = parts[1] ? start + ( parts[1] + 1 ) * end : end;
}
return tween;
}]
};